The acronym DTU stands for “unified technical document”. It is a document containing the rules and techniques to respect in construction. Respect for a DTU is not mandatory from a legal point of view. But without prior agreement from the insurer to waive a DTU, a possible disaster may not be supported.
Several DTUs concern the gutters. Thus, the DTU 60.11 sets the calculation methods for rainwater drainage systems. The DTU 40.5 recommends, for its part, the good rules for implementing these systems. DTUs are specific to the materials used for the gutter. For example, for zinc, refer to DTU 40, 41. DTU 43.1, for its part, concerns the evacuation of roof terraces.
Without strong building knowledge, some of the wording and technical terms presented in these technical documents may be difficult to understand. A zinc roofer is able to use the right products and put them, in accordance with the rules of DTU “gutters”.
Gutters: French and European standards
Gutters and their accessories may be marked NF. This is a voluntary initiative of the manufacturer. This marking certifies that the product corresponds to the needs of the consumer, according to a standard set up by industry professionals. It is issued by an independent body. A gutter that does not have the NF mark is not necessarily a gutter of lesser quality, but it will not benefit from the additional guarantee granted by this French standard.
In addition, when the construction product conforms to a European standard, it can receive the NF EN label, not to be confused with the CE marking certifying only that the product complies with the safety regulations and that it can be sold in the countries of the European Union.
For the rainwater drainage systems of the roof, many European and French standards are applicable. The NF P36-403 standard is, for example, the standard to be met by pipes, elbows and metal bowls to benefit from NF marking. The NF EN 607 standard defines the requirements and test methods for hanging gutters and their PVC fittings. For laminated metal, you will need to refer to NF EN 612.